孔隙介质热激活弛豫波动理论  

WAVE THEORY WITH HEAT EFFECTS IN POROUS MEDIA

作　　者：易良坤[1] 席道瑛[1] 刘小燕[1] 

机构地区：[1]中国科学技术大学地球及空间科学系和第三世界科学院地球科学及天文学高级研究中心,合肥230026

出　　处：《岩石力学与工程学报》2003年第5期803-809,共7页Chinese Journal of Rock Mechanics and Engineering

基　　金：成都理工大学国家重点(专业)实验室(PLC9906)基金;国家自然科学基金(40174050)

摘　　要：利用流变模型描述饱和多孔岩石的粘弹耗散,获得修正了的Debye方程和它的实模量与虚模量。假定孔隙介质符合Debye方程和Cole-Cole分布,将描述热激活弛豫过程的Arrhenius关系与局部流体流动理论结合,取得衰减峰的峰值频率对应的峰值温度,并将此引入Debye模型的复模量,得到孔隙介质热激活弛豫波动理论模型。为此探讨了激活能对复模量随频率和温度的影响。利用模拟退火Monte Carlo算法以及信号处理中增益控制的思想对目标函数进行了改进,从而对模型参数进行了反演。以低频共振实验数据对该理论模型进行了检验,理论模型与实验结果吻合,为Biot理论模型的低频修正奠定了基础。The rheologic model is adopted to describe visco-elastic attenuation in saturated porous rocks and the modified Debye's equation with real and imaginary modulus is obtained. Arrhenius equation is used to describe thermo-activated relaxation. Based on the assumption that porous materials follow Debye's equation and Cole-Cole distribution law. Arrhenius equation is combined with local fluid model to obtain the temperature on peak frequency. The wave model with heat effects in porous media is obtained when introducing peak temperature into Debye's equation. For this purpose it is discussed how the activation energy affects complex modulus changing with temperature and frequency. The control method is gained to establish the modified objective function, and annealing simulation and Monte Carlo algorithm are used to do inversion on the model. Verification with low frequency resonance data shows that the model is fine and the result can be a basis of low frequency modification on Biot's theory.

关 键 词：孔隙介质 热激活弛豫 波动理论 Debye方程 岩石 

分 类 号：TU452[建筑科学—岩土工程]